On Wed, Oct 30, 2013 at 7:01 PM, Cong Hou <co...@google.com> wrote: >>> I found my problem: I put DONE outside of if not inside. You are >>> right. I have updated my patch. >> >> OK, great that we put things in order ;) >> >> Does this patch need some extra middle-end functionality? I was not >> able to vectorize char and short part of your patch. > > > In the original patch, I converted abs() on short and char values to > their own types by removing type casts. That is, originally char_val1 > = abs(char_val2) will be converted to char_val1 = (char) abs((int) > char_val2) in the frontend, and I would like to convert it back to > char_val1 = abs(char_val2). But after several discussions, it seems > this conversion has some problems such as overflow converns, and I > thereby removed that part. > > Now you should still be able to vectorize abs(char) and abs(short) but > with packing and unpacking. Later I will consider to write pattern > recognizer for abs(char) and abs(short) and then the expand on > abs(char)/abs(short) in this patch will be used during vectorization.
OK, this seems reasonable. We already have "unused" SSSE3 8/16 bit abs pattern, so I think we can commit SSE2 expanders, even if they will be unused for now. The proposed recognizer will benefit SSE2 as well as existing SSSE3 patterns. >> Regarding the testcase - please put it to gcc.target/i386/ directory. >> There is nothing generic in the test, as confirmed by target-dependent >> scan test. You will find plenty of examples in the mentioned >> directory. I'd suggest to split the testcase in three files, and to >> simplify it to something like the testcase with global variables I >> used earlier. > > > I have done it. The test case is split into three for s8/s16/s32 in > gcc.target/i386. OK. The patch is OK for mainline, but please check formatting and whitespace before the patch is committed. Thanks, Uros.
